5-manipulation + spite Flashcards
what is manipulation?
an individual may be tricked or coerced into behaving cooperatively so what appears altruistic is actually manipulation
why is all behaviour likely to involve some degree of manipulation?
individuals try to selfishly maximise their own fitness at the expense of others
list 3 species that exhibit manipulative behaviour
- european starling
- cuckoo finch
- tawny flanked prinia
what is interspecific brood parasitism?
parasites exploit parental care of hosts to trick them to be altruistic
what indicates hunger in cuckoo parasites?
begging calls and brightly coloured gapes
who and when studied how cuckoos persuade host parents to care for their young
kilner et al 1999
what rate will host reed warblers feed a single cuckoo chick at compared to reed warbler chicks?
feed one cuckoo chick at a similar rate to 4 reed warbler chicks
in an experiments increasing the sound begging component how did parent reed warblers respond?
respond to a louder noise or bigger gape
how many reed warbler chick begging calls do cuckoo chicks mimic?
> 4
why are the gapes of cuckoo chicks at a disadvantage in terms of signal? - what makes up for this>
smaller than host brood
- begging calls: beg at higher rate than 4 reed warblers so parents feed more frequently
what can and cant cuckoos increase?
can increase call rate but not gape area
what do cuckoo chicks exploit?
behavioural rules of the parents as they initiate auditory and visual cues
what is the cost of begging at a high rate?
attracts predators
what is the brood parasitism example for horsfields hawk-cuckoo? (2)
- when hungry wave wings so yellow patch under its wing acts as a second gape so it doesn’t have to beg as loud to signal hunger
- only display false gape when more hungry
what did canestrari et al 2014 discover about great spotted cuckoo as an example of parasitism becoming mutualism?
- benefit hosts by emitting foul secretion that repels predators, increasing chance of host brood fledging
- parasitised groups had higher success rates
describe how there is a continuum of symbiotic interactions
coop interactions are unstable and turn into exploitation when one individual takes advantage of social partner
what does intra and inter specific conflict have power in generating?
adaptation to manipulate others to be altruistic towards them
describe the example discovered by Hojo et al 2015 for mutualism becoming parasitism (7)
- lycaenid butterfly and ants
- provide secretion that ants like meaning more likely to attend the larvae
- fed by ants in nest
- protect larvae from predators in return can feed from nectary organ of butterfly
- butterfly manipulates ants behaviour
- feeding ant can induce ants to spend less time walking so they defend more
- aggression induced in ants aiding in their defense as manipulative drug in secretion decreases dopamine in ants brain
in terms of hamilton’s rule when can spiteful behaviour evolve?
rB > C
relatedness must be negative
how is r negative?
- relatedness coefficient involves sharing genes identical by descent
- relatedness measured relative to population as a whole
when may a spiteful gene spread through a population?
if it harms individuals not carrying the gene therefore benefitting other carriers of the spiteful gene
what does spite directed at non relatives benefit?
relatives
give 5 facts about polyembryonic parasitoid wasps discovered by Giron et al 2004 and Gardner et al 2007
- M and F egg laid into moth larva
- clonal F and M larvae occupy single host
- egg divides asexually producing thousands of larvae
- some F develop at sterile soldiers, attacking other larvae
- soldier (F) relatedness to F is 1 as clonal and relatedness to M is 0.25
give 4 reasons why the behaviour in polyembryonic parasitoid wasps can be considered spiteful
- behaviour costly for sterile soldiers as give up ability to reproduce
- behaviour targets unrelated individuals/distant kin such as M
- close kin benefit from harmful behaviour, eliminating M larvae, increasing prob F larvae can emerge as adults
- F comp for resource provided by moth host reduced
in terms of kin what kind of mechanism is harder to develop?
to discover distant kin
give 3 reasons as to why spite is rare in nature
- spiteful act to non kin incurs cost to actor
- may benefit relative but also other unrelated individuals : so actor may derive net cost from spite
- hard to recognise small number of close kin but harder to recognise individuals with negative relatedness : risk that spiteful behaviour directed to distant kin as well as those of negative r
what provides the framework to understand the evolution of social behaviours?
hamilton’s concept of IFT and social interaction table
what is the default of NS?
selfish behaviour
why is spite rare?
unusual conditions required
altruism arising by what is likely to be selected for?
manipulation
describe Gardner and West 2006 findings for chemical warfare in bacteria (4) + 3 examples (3)
- some bacteria explode into antibacterial toxins to kill competitors
- closest relatives spared due to genetic linkage between toxin gene and gene giving immunity to toxin
- only negatively related cells killed
- health affected as if bacteria at war with each other they are less able to sustain infection
- e.g. p.luminsecens
- e.g. parasitoid wasp: wolbachia causes M to spitefully sterilise F
- e.g. suicidal soldiers in parasitoid wasps
what is greenbeard spite and an example of where it occurs (3)
- if r to victims of spite - then spite favoured by kin selection
- gene encoding distinctive trait/green beard genetically associated with spite gene then this marker can be used to guide relations
- in red fire ants where workers with spiteful gene kill prospective queens who don’t share gene: ensures surviving queens carry the gene
